Valve spring change time ?

[Elnef]

When is it time to change valve spring ?
How much lost pressure is okay ?
Lets say 190 build in and 500 with full lift
Is it time at 180 or 160 or ?

[dangerous]

There is no easy answer to this,
but a simple rule of thumb might be, if you can't restore the pressure with one .015" shim,
then time to change them.

If they have lost more pressure than this after one season,
you may need a better spring, or have an issue with the application.

[Erlend / bug66]

I would think that you change when you get valve float at a rpm you did not get it before?

I've run VW650 springs the last few years, and just replaced them each winter to be safe.

[richie]

K 800s?  if so their is a PSI spring that fits and seems to last much longer, more money but you know how that goes


cheers Richie

[Elnef]

wasco jet from pauter 

I have been looking at k motion homepage and there is a lot there will fit my set up
I belive its a good spring ?

[LGK]

John,

Just a question;are you running titanuim valves,and if yes what sizes?
Also i've noticed you are running JPM camshaft,other then if you're running a roller cam design from JPM,what did Johannes advice you to set up the springpackage on the heads?



Steve

[Elnef]

Hi Steve
I run normal cam solid lifter
Yes ti valves intake 52,82mm 84g exhaust  41,3mm 70g
Jpm lifter 94g Berg push rod 80g
Jpm advised 190/200 build in and 500 at max lift

Let me know what you are thinking

John

[neil68]

I would think that you change when you get valve float at a rpm you did not get it before?

I've run VW650 springs the last few years, and just replaced them each winter to be safe.

I started to experience valve float with my MS230 heads, after 160+ trips down the 1/4-mile drag strip.  I replaced them with VW650 springs (available locally) and have just over 100 races on those springs, so I'll see how that goes.  I must invest in a spring pressure tool one of these days.